21. Principles of Disease

The only genus of Gram-negative cocci that causes significant disease in humans is

a. Pasteurella

b. Salmonella

c. Klebsiella

d. Neisseria

Explain why E. coli is frequently implicated in cystitis in females.

Which of the following is not true about adhesin molecules?

Although an effective vaccine is available to eradicate pertussis in the United States, why has the number of reported cases increased since the 1970s?

Explain why Staphylococcus epidermidis is rarely pathogenic while the similar S. aureus is more commonly virulent.

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Show the location of the following diseases: common cold, COVID-19, diphtheria, coccidioidomycosis, influenza, pneumonia, scarlet fever, tuberculosis, and whooping cough.

True or False: Clostridioides difficile cases are usually associated with a prior antibiotic therapy.

A child comes into your clinic with impetigo. The lab cultures a sample for further analysis. If the sample is S. aureus, which lab results would you expect?

a. Gram-positive cocci in clusters, catalase and coagulase positive

b. Gram-negative diplococci, catalase positive, and coagulase negative

c. Gram-positive cocci in clusters, catalase negative, and coagulase positive

d. Gram-positive cocci in chains, catalase positive, and coagulase negative

e. Gram-positive cocci in chains, catalase negative, and coagulase positive

Given that pseudomonads are present in almost every moist environment, why do they cause less disease than other, less prevalent Gram-negative bacteria?

All of the following are phases of bacterial pathogenesis except which of these answers?

Compare and contrast cat-scratch disease and toxoplasmosis.

A patient with nausea, vomiting, and diarrhea within 5 hours after eating most likely has

a. shigellosis.

b. cholera.

c. E. coli gastroenteritis.

d. salmonellosis.

e. staphylococcal food poisoning.

Label inclusion, elementary, and reticulate bodies of Chlamydia: <IMAGE>

Which of the following is most controversial for a nonseptic patient with E. coli O157:H7?

a. Administering oral rehydration therapy

b. Administering antibiotic therapy

c. Administering fever-reducing medications

d. Administering intravenous rehydration therapy

e. Withholding agents like diphenoxylate-atropine that reduce GI tract motility